Terms to know: hypothesis, prediction, model, theory, homology, analogy, phylogeny, speciation, ring species, uniformitarianism, hierarchical pattern of homology, vestigial organ, the fossil record.

 Questions:

1. Why can hypotheses be disproved, but never proved?
2. How did Charles Darwin apply the principle of uniformitarianism in arguing that evolution can explain the origin and diversity of life?
3. What observation or observations could Darwin & Wallace's hypothesis of natural selection explain?  Give an example of a testable prediction of this hypothesis.
4. The following lines of evidence support the theory of evolution.  For each line of evidence: (i) clearly explain what the line of evidence is (define terms, explain what they mean, describe the pattern or experimental results), (ii) fully describe at least one example of this line of evidence (refer to both your lecture notes and your textbook), and (iii) clearly explain why this line of evidence supports the theory of evolution.
1. Observations of gene (allele) frequency changes in natural populations
2. The existence of ring species
3. The existence and hierarchical pattern of homology
4. The existence of vestigial organs
5. The near universality of the genetic code
6. Artificial selection experiments and selective breeding of domesticated plants and animals
7. The order of appearance of types of organism in the fossil record
5. Describe at least two lines of evidence that suggest that it is possible for there to be sufficient evolutionary change within a species to form new species so that speciation can occur.
6. Describe evidence that suggest that all organisms on earth have evolved from a single common ancestral species.
7. Describe evidence that evolution can occur within populations.
8. The main significance of the pattern of homology observed among species is that it is hierarchical.  Explain what this means and why it is significant.  To show that groupings of objects in general do not have to fit into nested hierarchies, come up with examples of ways of categorizing any objects and indicate whether or not they are hierarchical (you might consider the periodic table of the elements, the organization of files on a computer hard drive, and the way web pages are linked together on the world-wide web.)
9. From Freeman and Herron (2001), present two hypotheses that would explain the long necks of giraffes.  Discuss evidence used to question the original hypothesis presented and support the more recent hypothesis.
10. Three main methods used by evolutionary biologists to test hypotheses of the adaptive significance of traits are experiments, observational studies, and comparative studies.  For what kinds of situations/studies would each of these be the most useful?
11. In Greene et al's study of Zonosemata flies, state the hypotheses tested.  State the prediction(s) of each hypothesis that are tested.  Which hypothesis is supported by the results?  Explain how you know what is supported.  What makes an experimental study such as this one particularly powerful?  Does the fact that this hypothesis is supported using this powerful method mean that it is true?
12. What hypothesis is tested in Huey et al.'s study of garter snake thermoregulation?  State the prediction(s) of the hypothesis that are tested.  Is the hypothesis supported?  How can you tell?  This study is observational.  What can make observational studies less powerful than experimental studies?  In this case, what did Huey et al. do to make this a powerful observational study?
13. What hypothesis did Hosken test about testis size in bats?  What prediction did he test without considering phylogenetic relationships among the bats?  Clearly discuss the problems with such a test.  How did he test his prediction while considering phylogenetic relationships among bats?  Why is this a better test?
14. Use the example in Freeman and Herron (2001) of the evolution of the bones in the mammalian ear to discuss the importance of considering that every adaptive trait evolves from something else
15. Use the example of flower color change in fuschias to illustrate the concept of physiological constraint
16. Use the example of host shifts in herbivorous beetles to illustrate the concept of constraints resulting from lack of genetic variation